Chickens are losing feathers around vent

[abigalmarie02]

I have ten chickens and most of them are experiencing a lose of feathers around their vents as shown in the pictures. Only one chicken is experiencing a lose of feathers around the head. It started off with only two of them looking like this so I thought it was mites and I treated them for that for a week. I used a mite spray that I bought from tractor supply, I spread diatomaceous earth, and cleaned out the coop completely. Now that it is spreading into the rest of the flock, I am not sure that it is mites anymore. Any suggestions for what it might be and what to do to treat it are welcome!
!

 

[Eggcessive]

It looks like feather picking which can become a habit, and possibly lead to cannibalism. What type of feed do you give them? Feeding to low of a diet in protein, overcrowding, boredom, and not getting out to free range can be common causes of feather picking. I would not treat for lice or mites unless you actually see them. Feeding a good 16% protein layer feed is the minimum for laying hens. Some use a 20% flock raiser feed and supplement calcium with crushed oyster shell. Corn, scratch or table scraps should be very limited, or they will not be getting proper nutrition or enough protein.

 

[Unexpected chicken lover]

It looks plucked to me...im no expert, but do they get along? Are they on a high protein feed? Crowded? Anything you can think?

More experienced chicken handlers will come along and help. But they will ask these questions

 

[Labradors]

I am new at this, but you could read up about lice. I am going through the same thing and I suspect that it could be lice. I used dusting powder (good for lice and mites) on the chicken butts, cleaned and dusted the coop with D.E., and will repeat after 10 days to catch any newly-hatched eggs. Don't forget to dust the roosting bar with D.E.

Good luck!

 

[abraga]

Looks like feather picking to me to> I agree w/eggcessive> up the protein. I feed flock raiser w/oyster shell. Are they penned up? If so...how many chickens per square foot? What breed? Overcrowding ..heat...boredom ..confinement may lead to feather picking..some breeds don't bear confinement as well as others.